Process for forming yarns



Patented Mar. 1, 1949 FFICE Robert Burgess, Jr., Wilton, Conn.

No Drawing. Application May 8, 1943, Serial No. 486,208

This invention relates to the art of making yarn V staple fibers, takingthe cotton system of spinning as an example. the cotton fibers arecarded, and then formed into sliver, which is a continuous strand ofloosely matted fibers. Two or more slivers are then doubled and drawnone or more times and twisted slightly to form roving, which is also acontinuous strand of fibers, but in which the fibers are somewhat moreclosely matted than in the sliver stage, due, in part, to the slighttwist imparted. Two or more rovings are then doubled and drawn one ormore times and are then twisted considerably to form yarn. The abovesteps are varied, of course, depending on the particular type of yarnbeing made, but in general it is true that in the case of themanufacture of yarn from staple fibers by the cotton system of spinningthe succession of stages between fibers and yarn includes sliver androving stages. By staple fibers I mean fibers of determinate, relativelyshort length such as cotton fibers, for example, as distinguished fromfibers in the form of continuous filaments of indeterminate length suchas silk or various synthetic fibers such as rayon or nylon for example.The process of my invention as hereinafter described is limited to usewith staple fibers as above defined which are susceptible of beingdoubled and drawn in the rovin stage. However, in addition to naturalstaple fibers, I include synthetic or natural fibers originally incontinuous filament form which have been cut to staple length and whichare customarily formed into yarn by using the cotton system of spinning,as for example the staple rayon fibers now used in the manufacture ofso-called spun rayon yarn, for such fibers may be and customarily aredoubled and drawn in making yarn therefrom.

In the sliver stage the strand formed from such staple fibers isexceedingly fragile and tenuous. It cannot be wound on a bobbin andcannot be safely handled without danger of damagin or breaking thestrand. In the roving stage, however, the strand is considerablystronger and after reaching this stage may be, and customarily is, woundon a bobbin. In the sliver stage the doubling and drawing operations areusually performed on drawing frames, and the transition from sliver toroving is usually made in machines known as slubbers, which in additionto doubling and drawing the strand, impart a slight twist as the rovingis wound on the bobbin. Subsequent doubling and drawing operations areusually performed in fiy frames and roving frames, sometimes 5 Claims.(Cl. 57-156) called intermediates and finally the roving is transferredto a spinning frame where the final yarn making steps are performed.Such steps customarily include doubling, drawing and twisting.

In the manufacture of colored fabrics it is customary either to dye thefibers before carding (stock dyeing), or to dye the yarn before weaving(yarn dyeing), or to dye the fabric after weaving (piece dyeing),roving, in practice roving which is to be subsequently.used for makingyarn is seldom dyed as there has heretofore been no particular advantagein so doing except for special purposes.

Stock dyeing is considerably more expensive than yarn dyeing or piecedyeing, and has no advantage over yarn dyeing, for example, if the yarnis to be formed from fibers of a single color. Stock dyeing has beenconfined for the most part, therefore, to the making of woolen-yarn,where it has long been known that very beautiful color effects may beobtained in the yarn, and thereafter in fabric woven therefrom, bymixing or blending different colored fibers, and thereafter formingyarn'therefrom by the usual processes. The successful blending of suchdifferent colored fibers requires great skill, however, and the practicehas seldom been used in the making of yarn from fibers other than woolenfibers.

Thus, in the manufacture of cotton fabrics, dyeing has been confined forthe most part to the dyeing of yarn before weaving or dyeing of thefabric after weaving, and with the exception of woolen fabrics this isgenerally true of colored fabrics. One variation may be mentioned,however. It is known that viscose rayons and acetate rayons reactdifferently to some dyes. For example, viscose rayons will not acceptcertain. dyes which are accepted by acetate rayons and vice versa. Inthe manufacture of spun rayon yarns, therefore, made from staple fibers,it has been well known practice to mix staple viscose rayon fibers withstaple acetate rayon fibers and to form yarn from such mixtures by usualmethods. Then the yarn has been subjected to a dye which is accepted bythe viscose fibers, for example, but not by the acetate fibers, resultinin a yarn containing a blend of dyed viscose fibers and undyed acetatefibers. Such yarn is sometimes used for weaving in that state. Othertimes the yarn is subjected to a second dye of a different color whichis accepted by the acetate fibers, but not by the viscose fibers, thusresulting in a yarn containinga blend of fibers of different colors, theviscose fibers being of one color and the acetate and while it ispossible to dye fibers being of a different color. Similar results maybe obtained by piece dyeing a fabric woven from yarns containingmixtures of viscose and acetate rayon fibers. Such processes, however,are usually limited to two colors.

It is an object of the present invention to provide a process for makingyarns containing fibers of a plurality of different colors, which saidprocess may be carried out by existing machines and with only'slightvariation of existing practices now used in the cotton system ofspinning, whereby the beautiful effects of blending different coloredfibers in making woolen yarn, and which are achieved only at costs whichare prohibitive in yarns made from cheaper materials, can be obtained atcosts comparable to those of ordinary dyed yarn, thus opening upentirely new possibilities of novel and beautiful color effects incotton fabrics, for example.

Other objects and advantages of the invention will appear hereinafter.

According to the present invention, I proceed according to presentpractices prevailing in the cotton system of spinning up to the stagewhere roving is formed, that is, sliver is formed from carded fibers,and then by the usual methods of doubling and drawing, together withslight twisting, roving is formed, and wound on bobbins. At this point,however, before proceeding with the subsequent operations customarilyperformed to form yarn, such roving is then dyed by any suitable method,preferably by package dyeing as commonly practiced.

In the simplest form of the invention two rovings of different colorsare then selected,. which said rovings are then doubled and drawntogether. In the process of doubling and drawing, the fibers of oneroving become intermingled with the differently colored fibers of theother roving, so that a dispersion and mixture of the difierentlycolored fibers occurs throughout the strand.

In another form of the invention three, four or more rovings each of adifferent color may be selected, which said rovings are doubled anddrawn together as before with resulting intermingling of the fibers ofdifferent colors. Alternatively, two rovings of one color and one ormore rovings of different color may be selected and doubled and drawntogether as before with resulting intermingling of the fibers ofdifferent colors.

After having thus effected the initialintermingling of the fibers ofdifferent color, the resulting roving may be doubled and drawn togetherwith a similar roving having similarly intermingled fibers of differentcolor. For example, a roving of color a may be doubled and drawn with aroving of color 1), resulting in a roving having intermingled fibers ofcolor a+b,' while simultaneously a second roving of color a may bedoubled and drawn with a second roving of color b, resulting in a secondroving having intermingled fibers of color a+b. The two rovings each ofcolor a+b may then be doubled and drawn together. In this case thesecond doubling and drawing operation results in a still more thoroughintermingling of the fibers of different color, and it will beunderstood that repeated doubling and drawing of similar rovings willincrease the thoroughness of the intermingling of the fibers ofdifferent color. a

Similarly rovings of colors 41, b, c, d may be doubledand drawntogether, resulting in a roving having intermingled fibers of colora+b+c+d. Such roving may then be doubled and'drawn with a second rovinghaving intermingled fibers of color a+b+c+d, or three or four rovings ofcolor a+b+c+d may be doubled and drawn together. In either. case thethoroughness of intermingling 'of the fibers of different color isincreased. In the event that limitations of available machinery make isinconvenient to double and draw together more than two rovings, a

roving of color a may be doubled and drawn' cal cotton mill practice,roving is customarily.

subjected to several doubling and drawing operations before being placedin a spinning frame for the final yarn making operation. As willbeunderstood from the foregoing description, one of these operations ascustomarily practiced may be utilized to effect the initialintermingling of the fibers of different color, and the subsequentdoubling and drawing operations as usually performed may be utilized toincrease the thoroughness of the intermingling, or an extra doubling anddrawing operation may be utilized to effect the initial intermingling ofthe fibers of different color, and the subsequent doubling and drawingoperations as usually performed may be used to increase the thoroughnessof the intermingling.

As a specific example of the latter, and illustrating the manner inwhich an extra operation may be adapted to typical cotton mill practice,the following may be considered. As previously stated, I proceed to formroving in the usual manner, using the usual drawing frames and slubbersfor this purpose. Such roving might be prefer: ably taken off theslubbers as approximately 1.6 hank roving, as such roving issufiiciently strong to withstand the dyeing operation, and yet has solittle twist that subsequent intermingling will be facilitated. Suchroving is then dyed in whatever colors are desired.

Assuming then that it is desired to form a yarn containing fibers ofcolors a, b, c and d,

roving of each of these colors is selected, and the four ends aredoubled and drawn together as an extraoperation. Preferably thisoperation is so conducted that the single roving produced is ofapproximately the same size as each of the rovings introduced, 1. e. 1.6hank roving, and having approximately the same twist. That is, in theexample given in which four ends are introduced, the doubled rovingwould be given a draft of four.

Any suitable machine may be used for this purpose, but for convenience,I suggest the use of a specially adapted slubber or fly frame. Inpackage dyeing,.the-material to be dyed is customarily wound onso-called "springs which are shaped somewhat like short bobbins, butcomprise a tubular knitted fabric stretched taut by a spring, which saidfabric serves as the cylindrical base on which the material is wound. By

adapting a slubberor fly frame to receive such duces substantial fibersof color a+b+c+d is wound on bobbins, of course, and from this point on,the mill procedure is as usual. In each subsequent doubling and drawingoperation the rovings which are doubled and drawn together are ofsimilar color characteristics.

The advantage of the above procedure lies in the fact that the doublingand drawing operation which produces the initial intermingling of thefibers of different color results in a roving of substantially the samesize and twist as the original undyed roving, so that for any givenyarnthe ordinary mill procedures do not need to be altered in any way.In cases where the roving is sent to a dye plant for dyeing, it wouldthus be possible for the dye plant to perform the extra doubling anddrawing operation before returning the roving to the mill, so that ifthe mill sent out 1.6 hank undyed roving, it would receive back 1.6 hankroving containing intermingled fibers of different colors.- Such rovingwould then be handled in the ordinary way until formation of the yarnwas completed.

Many other specific variations might be described, but it will beapparent from the foregoing that the common features of variousexemplifications of the invention are (1) dyeing the strand while in theroving stage before the strand has been twisted sufflciently to preventsubsequent intermingling of the fibers of one roving with those ofanother roving, (2) utilizing subsequent doubling and drawing of rovingsof different color to cause intermingling of the fibers of one colorwith the fibers of another color, and (3) after thus efiecting theinitial intermingling of fibers of different color, utilizing subsequentdoubling and drawing of rovings of similar color characteristics toincrease the thoroughness of the intermingling, all such operationsbeing performed prior to transfer to the spinning frame to form a yarn.

I am aware that in the past a yarn of one color has been twisted with ayarn of a difierent color to form a plied yarn, but the effect of thisprocedure is wholly different from that obtained in the practice of myinvention. Where two yarns are twisted together there is nointermingling of the fibers of diiferent color. The effect obtained maybe roughly described as a striped or "barber pole effect, for the yarnof one color simply alternates with the yarn of the other color, thetwist in the individual yarns preventing any intermingling of thefibers. Fabrics woven from such yarns present a somewhat speckledappearance.

I am also aware that in the past two rovings of different color havebeen supplied to a spinning frame and twisted together to form a yarn.Here again the effect is wholly different from that obtained in thepractice of my invention. By the time the roving has been attenuatedsulficiently to be used on a spinning frame the strand is fine andtwisted to an extent suchas to prevent intermingling of the fibers asthey pass through the drawing rollers of the spinning frame. The efiect,therefore, is similar to that obtained by twisting two yarns ofdifferent color, namely, a striped or barber pole effect as abovedescribed. In fact, this practice has been employed to imitate, at lowercost, the effect of twisting two yarns of different color.

As contrasted with such striped effects, the intermingling oi the fibersof different color, according to the practice of my invention,=prouniformity of dispersion throughout the yarn and a softness andrichness of color effect which greatly enhances the beauty of fabricswoven from such yarns. Such fabrics provide a depth of color and avisual color interest wholly lacking in fabrics made from ordinary dyedyarn or in piece dyed fabrics.

In the foregoing description where I have referred to the use of rovingsof difierent colors I include the use of rovings of difierent shades ortints of the same color. For example, a yarn may be formed of roving ofdifferent shades or tints of brown, different shades or tints of bluewithin the scope of my invention. Furthermore, I include the use of oneor more rovings of natural (undyed) color with one or more dyed rovings.For purposes of this specification, therefore, I intend the phrasedifferent color to include such variations.

It will be understood that the invention may be variously modified andembodied within the scope of the subjoined claims.

I claim as my invention:

1. In the cotton system for forming yarn from staple fibers of cotton orrayon, the process for forming yarn containing intermingled fibers of aplurality of different colors which comprises forming a plurality ofrovings from staple fibers, dyeing at least one of said rovings a colordifferent from that of at least one other of said rovings, doubling anddrawing said rovings of different color to form a roving in which thefibers of the rovings of different color are intermingled, thereafterrepeatedly doubling and drawing said roving with another similarlydoubled and drawn roving of similar color characteristics to increasethe thoroughness of the intermingling, and spinning the resulting rovingto form a yarn.

2. In the cotton system for forming yarn from staple fibers of cotton orrayon, the process for forming yarn containing intermingled fibers of aplurality of different colors which comprises forming a plurality ofrovings from staple fibers, dyeing said rovings a plurality of differentcolors, doubling and drawing a roving of one color with at least oneother roving of difierent color to form a roving in which the fibers ofdifferent color are intermingled, thereafter repeatedly doubling anddrawing said roving with another similarly doubled and drawn roving ofsimilar color characteristics to increase the thoroughness of theintermingling, and spinning the resulting roving to form a yarn.

3. In the cotton system for forming yarn from staple fibers of cotton orrayon in which the fibers are processed successively in drawing frames,slubbers, intermediates and spinning frames, the process for formingyarn containing intermingled fibers of a plurality of different colorswhich comprises carrying undyed fibers through such drawing frames andslubbers and forming rovings from such fibers in such slubbers, dyeingsuch rovings a plurality of different colors, doubling and drawing aroving of one color with at least one roving of different color at astage prior to said intermediates to form a roving in which the fibersof different color are intermingled, thereafter carrying said rovingthrough said-intermediates and repeatedly doubling and drawing saidroving in said intermediates with another similarly doubled and drawnroving of similar color characteristics to increase the thoroughness ofthe intermingling, and spinning the re sulting roving to form a yarn.

4. In the cotton system for forming yarn from staple fibers of cotton orrayon in which the fibers are processed successively in drawing frames,slubbers, intermediates and spinning frames, the process for formingyarn containing intermingled fibers of a plurality of different colors.which comprises carrying undyed fibers through such drawing frames andslubbers and forming rovings from such fibers in such slubbers, dyeingsuch rovings a plurality of different colors, doubling a plurality ofrovings of diflerent color and drawing said rovings to form a roving ofa hank size not less than that of the rovings introduced and in whichthe fibers of different color are intermingled, thereafter repeatedlydoubling and drawing said roving with another similarly doubled anddrawn roving of similar hank size and similar color characteristics toincrease the thoroughness of the intermingling while reducing the hanksize on each draft, and spinning the resulting roving to form a yarn.

5. In the cotton system for forming yarn from staple fibers of cotton orrayon in which the fibers are processed successively in machines whichdraw the fibers without twisting and deliver a strand in sliver form,then in a machine which draws the sliver strands, imparts twist theretoand delivers a strand in roving form, then in machines which draw theroving strands, impart additional twist thereto and again deliver astrand in roving form, then in a machine which draws the roving strands,imparts additional twist thereto and delivers a strand-in yarn form, theprocess of forming yarn containing intermingled fibers of a plurality ofdifferent colors which comprises carrying undyed fibers through suchmachines to the stage where rovings are delivered,

dyeing such rovings, then doubling and drawing a strand of roving of onecolor with at least one strand of roving of different color in a machinewhich draws the strands, imparts twist thereto and delivers a strand ofroving in which the fibers of diflerent color are intermingled,

thereafter repeatedly doubling. and drawing said strand of roving withanother similarly doubled REFERENCES CITED The following references areof record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,058,620 Petitimermet Oct. 2'1,1936'" FOREIGN PATENTS Number Country Date 25,611 Great Britain 1903OTHER REFERENCES Technical Terms in the Textile Trade, by Midgley;published by Emmott & Co. Ltd., Manchester, England? pages 152-153.

Textile Design and Color, by Watson; published by Longmans, Green 8:00., London, England; Pa es 144145.

